Severn Trent VAX4600 Series, Instruction Manual

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115.6001.10

t.

 Install the chamber into the water bath tank in proper orientation and fasten in place with the eight
bolts around the top plate. Replace the rubber gasket if required.

u.

Insert a new lead gasket into the groove in the chamber flange.

v.

Install the chamber flange into the chamber.

w. Insert the twelve 3/4" bolts into the chamber flange and apply 110 FOOT-POUNDS TORQUE. Make

sure to torque opposite bolts sequentially.

x.

Reconnect wiring to anodes and ammeter. Refer to Cathodic Protection Section VIII.

y.

Insert gas temperature and pressure sensors into their protective wells.

z.

Prepare the vaporizer for startup. Refer to Pre-startup Section.

aa. Start up the vaporizer. Refer to Startup Section.

4.2.2

Replacement Criteria

After the chamber has been cleaned both inside and outside of all deposits and ferric chloride, the
chamber should be weighed and inspected for excessive corrosion pitting to determine if it is still
safe for continued use.

When new, the chamber weighs 200 pounds (90.7 kilograms) and has an inside diameter of 5.761"
(146.3 mm). the chamber should be replaced if it exhibits a loss over 15 pounds (6.8 kilograms), or if
any pitting deeper than 0.125" (3.17 mm) can be measured.

Any vaporizer chamber which does not exceed these losses can be considered safe for continued
use.

a.

Gas Filter

While the vaporizer is shutdown for chamber cleaning, it is advisable that the filter (Y-strainer or
cartridge) in the gas line between the vaporizer and the pressure reducing valve be
disassembled and cleaned. Refer to the manufacturer’s instructions.

1.

Loosen fasteners housing the strainer or cartridge.

2.

Wash the strainer in hot soapy water. discard the cartridge.

3.

Dry the strainer completely.

4.

Reinstall cleaned strainer or new cartridge using a new lead gasket.

4.3

Heater Replacement

If the vaporizer requires longer than normal warm-up times or, if the full vaporization capacity cannot be
achieved, one or more heating elements may have failed.

Before inspecting the heaters, check the fuses in the power supply for failure.

To inspect the heater elements, FIRST TURN ELECTRICAL POWER OFF to the vaporizer heater and control
circuit. Then open the door on the heater enclosure. Disconnect the two wires to each heater element and, using
an ohmmeter, measure the resistance across the terminals. Infinite resistance indicates a faulty heater. Refer to
Figure 10 and proceed as follows to replace the heater element.

4.3.1

Shut off the manual gas discharge valves downstream of the vaporizer and shut down the process
equipment.

4.3.2

Open the 1" drain valve and drain the water from the water bath tank. Close the valve when the tank is
empty.

4.3.3

Close the manual filling valve.

4.3.4

Open the heater enclosure door and disconnect the two wires to the bad heater element.

4.3.5

Using a 1-1/2“ socket wrench, unscrew the heater element. Remove the element and gasket.

4.3.6

Install the new heater element and gasket. Be sure the new element is the same electrical rating as the
old one, per the markings on both parts.

NOTE:

 The heater elements must be aligned vertically for proper operation. Note the “UP" molded in the

face of the heater at installation.